U.S. patent number 7,540,094 [Application Number 11/240,724] was granted by the patent office on 2009-06-02 for cutter knives for slash-quilts.
This patent grant is currently assigned to Olfa Corporation. Invention is credited to Shoji Okada.
United States Patent |
7,540,094 |
Okada |
June 2, 2009 |
Cutter knives for slash-quilts
Abstract
A cutter knife for making slash-quilts is provided, which has a
plurality of guide members having different width dimensions.
Further, a plurality of slits are formed between each of the guide
members and the casing of the cutter knife, in each of the slits a
blade edge is exposed. Since one cutter knife is provided with a
plurality of guide members having different widths, the one cutter
knife can be widely used for making a variety of slash-quilts
having different pitch widths between stitch lines, without need
for exchanging the guide members. A user can select one guide
member having a suitable width dimension for a certain pitch width
between the stitch lines, and insert the selected guide member
between the stitch lines of a quilt. Then, the user pulls the
cutter knife backward to himself, or pushes it forward to cut the
quilt, and the slash-quilts is made.
Inventors: |
Okada; Shoji (Sakai,
JP) |
Assignee: |
Olfa Corporation (Osaka-shi,
Osaka, JP)
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Family
ID: |
36651732 |
Appl.
No.: |
11/240,724 |
Filed: |
September 29, 2005 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20060150426 A1 |
Jul 13, 2006 |
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Foreign Application Priority Data
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Jan 11, 2005 [JP] |
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2005-003543 |
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Current U.S.
Class: |
30/287;
30/294 |
Current CPC
Class: |
B26B
29/06 (20130101); B26B 25/005 (20130101); Y10T
83/4667 (20150401) |
Current International
Class: |
B26B
29/00 (20060101) |
Field of
Search: |
;30/2,206,240,263,264,286,287,288,289,293,294,292,282,306,307,317,319
;D8/98,102 ;83/466.1,821,829 ;144/176,218 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Payer; Hwei-Siu C
Attorney, Agent or Firm: Crowell & Moring LLP
Claims
What is claimed is:
1. A cutter knife for slash-quilts, comprising: a planar casing; a
plurality of guide members extending outwardly from the outer
peripheral portion of the casing and in a direction substantially
parallel to the plane of the casing and terminated at a free end,
wherein each of the plurality of guide members has a different
width dimension and wherein the width dimension extends
perpendicular to the plane of a rotary blade which is mounted in
the casing and substantially parallel to the plane of the casing;
and a plurality of slits formed between each of the guide members
and the casing of the cutter knife, in each of the slits a blade
edge which is formed along the periphery of the rotary blade is
exposed, and wherein a slash-quilt is receivable within the
plurality of slits and is cut by the blade edge.
2. The cutter knife for slash-quilts of claim 1, wherein: at least
one of the guide members is provided with a cut portion extending
in a longitudinal direction of the guide member, by which the width
dimension of the guide member is elastically changed under an
external force.
3. The cutter knife for slash-quilts of claim 1, wherein: the
casing of the cutter knife holds the rotary blade; the guide
members are provided at outer peripheral portion of the casing,
extending in parallel to respective tangential line to the rotary
blade; and an edge of the rotary blade is exposed in each of the
slits.
4. The cutter knife for slash-quilts of claim 3, wherein: the
casing of the cutter knife is formed in circular shape or regular
polygonal shape.
5. The cutter knife for slash-quilts of claim 3, wherein: all of
the guide members extend in a same direction, clockwise or
counterclockwise direction, relative to the casing of the cutter
knife.
6. The cutter knife for slash-quilts of claim 3, further
comprising: a handle coupled to the casing so that a user can grasp
the handle and conduct a cutting operation with the cutter
knife.
7. The cutter knife for slash-quilts of claim 3, further
comprising: a holder, coupled to the casing such that one of the
guide members and one of the slits associated thereto are exposed
to external at minimum, and which a user grasps to conduct a
cutting operation with the cutter knife.
8. The cutter knife for slash-quilts of claim 3, wherein: the
rotary blade is held by the casing of the cutter knife, in a
superposed condition with a blade cover, the blade cover having at
least the same diameter as that of the rotary blade, and a cutout
portion being formed at outer peripheral portion of the blade
cover, in which an edge of the rotary blade is exposed; a dial
member is provided on a side face of the casing of the cutter
knife, which is connected to the rotary blade and is intended for
rotationally driving the rotary blade in both of a first and a
second directions to adjust the angular position of the rotary
blade; the blade cover is associated with the casing of the cutter
knife via a first ratchet mechanism, such that the blade cover can
rotate relative to the casing in the first direction and can not
rotate relative to the casing in the second direction; the dial
member is associated with the blade cover via a second ratchet
mechanism, such that the dial member can rotationally drive the
blade cover in the first direction and can not rotationally drive
the blade cover in the second direction; when the dial member is
rotated in the first direction relative to the casing of the cutter
knife, the rotary blade and the blade cover together rotate in the
first direction, so that a portion of the blade edge exposed in the
cutout portion of the blade cover can be located in a desired one
of the slits; and when the dial member is rotated in the second
direction relative to the casing of the cutter knife, the rotary
blade is rotated in the second direction relative to the blade
cover, so that another portion of the blade edge can be exposed in
the cutout portion of the blade cover.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to cutter knives for
slash-quilts.
2. Description of the Related Art
Fancy cloths called slash-quilt are known as materials for porches,
bags, etc. As shown in FIG. 1, a slash-quilt cloth is made by
superposing a plurality of cloths on one another, stitching them
along a plurality of parallel stitch lines 6, and cutting the
layers of cloths 5a between the parallel stitch lines 6 (see the
arrow "X" in FIG. 1) except the lowermost layer 5, which is not cut
and left to remain. The slash-quilt cloth thus obtained has unique
and bulky feeling, or beauty.
As one of the cutter knives for making such slash-quilt cloths, a
cutter knife disclosed in Japanese Utility Model Registration No.
3048727 is known. In the cutter knife disclosed in Japanese Utility
Model Registration No. 3048727, the guide member for leading the
cutting direction while an user is cutting a cloth is formed
integrally with the casing of the cutter knife or is screwed to the
casing of the cutter knife. Therefore, the replacement of the guide
member is impossible, or may be burdensome.
In making of a slash-quilt cloth, it is desirable that the
dimension of the overall width of the guide member is substantially
equal to the pitch width between the parallel stitch lines 6, in
order to smoothly cut the upper cloths 5a under a proper tension.
On the other hand, the dimensions of the pitch width between the
parallel stitch lines 6 will vary in many kinds of slash-quilts.
Therefore, it is desirable to easily exchange the guide member for
other ones having a various dimensions of overall width.
According to the cutter knife in Japanese Utility Model
Registration No. 3048727, in the case that the guide member is
formed integrally with the casing of the cutter knife, it is
impossible to exchange the guide member of the cutter knife for
other ones. Otherwise, in the case that the guide member is screwed
to the casing of the cutter knife, exchange of the guide member for
other ones is burdensome. Therefore, the cutter knives disclosed in
Japanese Utility Model Registration No. 3048727 are unsuitable for
widely use in making a variety kinds of slash-quilt cloths having
different pitch widths between the stitch lines.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a
cutter knife for slash-quilts, with which a plurality of guide
members having different width dimensions can be utilized, without
exchanging the guide members.
In order to achieve the object of the present invention, there is
provided a cutter knife for slash-quilts, comprising: a plurality
of guide members having different width dimensions, which are
formed on a casing of the cutter knife; and a plurality of slits
formed between each of the guide members and the casing of the
cutter knife, in each of the slits a blade edge is exposed.
The cutter knife for slash-quilts of the present invention
constructed as above is provided with a plurality of guide members
having different widths. Therefore, it becomes possible to widely
use one cutter knife to make a variety of slash-quilts having
different pitch widths between stitch lines, by appropriately
selecting a suitable one guide member from the plurality of guide
members. For which, there is no need for exchanging the guide
members.
Between each of the guide members and the casing of the cutter
knife, there is provided a slit, and a blade edge is exposed in the
slit. Thus, a user can select one guide member having a suitable
width dimension, and insert it between the stitch lines of a quilt.
Then, the user pulls the cutter knife backward to himself (or,
pushes it forward) to cut the quilt.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and features of the present invention will
become apparent from the following description taken in conjunction
with the preferred embodiments thereof with reference to the
accompanying drawings.
FIG. 1 is a partial perspective view of a slash-quilt cloth.
FIG. 2 is an exploded perspective view of a cutter knife according
to the first embodiment of the present invention.
FIG. 3 is a front view of the cutter knife shown in FIG. 2 after
assembled.
FIG. 4 is an explanatory view showing the practical use of the
cutter knife shown in FIG. 3.
FIG. 5 is a perspective view of the cutter knife shown in FIG.
3.
FIG. 6 is a perspective view of a modified embodiment of the cutter
knife, which is provided with a handle.
FIG. 7 is a perspective view of another modified embodiment of the
cutter knife, which is provided with a holder.
FIG. 8 is a front view of the cutter knife shown in FIG. 7 after
assembled.
FIG. 9 is an exploded perspective view of a cutter knife according
to the second embodiment of the present invention.
FIG. 10 is an exploded perspective view, showing a part of FIG. 9
from the opposite side.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Hereinafter, the embodiments of the present invention will be
explained in detail with reference to the accompanying
drawings.
First Embodiment
FIG. 2 shows an exploded perspective view of a cutter knife 1 for
slash-quilts according to the first embodiment of the present
invention, and FIG. 3 shows a front view of the assembled cutter
knife 1.
Between two casing members 10a and 10b which constituting the
casing 10 of the cutter knife 1, a rotary blade 15 is held. The two
casing members 10a, 10b and the rotary blade 15 are assembled using
a screw member 12, an annular plate member 17, a washer 18, and a
nut 19.
As is well understood from FIG. 3, the cutter knife 1 is provided
with four guide members 21, 22, 23 and 24, at the outer peripheral
portion of the casing 10, which holds the rotary blade 15. All the
guide members 21 to 24 have different widths ("W" in FIG. 5) from
one another, and extend in parallel to the respective tangential
line to the rotary blade 15. As can be seen in FIG. 5, the width
dimension "W" extends perpendicular to the rotary blade. Slits 21a
to 24a are formed between the guide members 21 to 24 and the casing
10, respectively, and the edge 15a of the rotary blade 15 is
exposed in the respective slits 21a to 24a.
<<Manner of Use>>
In making a slash-quilt cloth, a user selects appropriate one guide
member, from the four guide members 21 to 24, of which the width
dimension fits the pitch width between the stitch lines 6. Then,
the user inserts the selected guide member 21 between the stitch
lines 6 of the quilt, and thus the slash-quilt within the slit 21a,
and pushes the cutter knife 1 forward (or backward toward the user)
so as to cut the quilt.
By using the selected guide member, it becomes possible to smoothly
cut the quilt under a proper tension and also to correctly cut the
quilt in straight along the center line between the stitch
lines.
Since there is a variety sizes of the pitch width between the
stitch lines 6, it is advantageous to selectively use a plurality
of guide members having different widths. In the shown embodiment,
the four guide members 21 to 24 having different widths ("W" in
FIG. 5) are provided on one cutter knife 1. Thus, the user can
appropriately select one suitable guide member from the four,
depending on the pitch width between the stitch lines of the quilt,
and cuts the quilt using the selected guide member, wherein
exchanging of the guide members is not needed.
<<Cut Portion Provided in Guide Member>>
FIG. 5 shows the perspective view of the cutter knife 1 shown in
FIGS. 2 and 3. The guide member 21 has a cut portion 29 formed
therein, extending along its longitudinal direction. With such the
cut portion 29 formed in the guide member 21, the width dimension
"W" of the guide member 21 can elastically change, when an external
force is applied from the outside to the inside of the guide
member.
The guide member is one inserted between the stitching lines 6 of
the quilt to apply a proper tension to the quilt to be cut. Thus,
it is preferable that the width dimension "W" of the guide member
is equal to or a little smaller than the pitch width between the
stitching lines 6. When the cut portion 29 is not provided in the
guide member, the width dimension "W" of one guide member is
unchanged, and therefore, the pitch widths between the stitch lines
to which such one guide member can be applied are limited.
On the other hand, when the cut portion 29 is provided in the guide
member, it becomes possible to reduce the width dimension "W" of
the guide member by the elastic deformation of the guide member,
even if the width dimension "W" before the deformation is slightly
larger than the pitch width between the stitching lines. Therefore,
one guide member can be applied to some variation of pitch widths
between the stitching lines, having some flexible range.
Since a plurality of guide members having different widths are
provided to the cutter knife in the present invention, the cut
portion 29 is not necessarily formed to the guide members. However,
with such the cut portions formed to the guide members, in
cooperation with the plurality of the guide members, one cutter
knife would be applied to increased kinds of quilts having various
pitch widths between stitch lines, so that the cutter knife can be
more widely used. Therefore, it is preferable to form the cut
portions to all of or at least some of the guide members.
<<Shape of the Casing of the Cutter Knife>>
In the shown embodiment, the casing 10 of the cutter knife is
shaped in circular, and the four guide members 21 to 24 are
provided at regular intervals on the outer peripheral portion of
the casing 10. In the cutter knife 1, one rotary blade 15 is
commonly used for the plurality of the guide members to cut a
quilt, and thus, the distances between the center of the casing 10
and the respective guide members are substantially equal to one
another. Accordingly, the circular shape is preferable for the
casing 10 of the cutter knife 1. However, the shape of the casing
10 is not limited to a particular one. For example, other than the
circular shape, regular polygonal shapes or other suitable shapes
can be employed for the casing 10 of the cutter knife 1.
<<Number, Direction and Interval of the Guide
Member>>
In the shown embodiment, the cutter knife 1 is provided with the
four guide members 21 to 24. That is, a user can utilize the guide
members of different 4 kinds of widths with one cutter knife,
without exchanging the guide members.
However, the number of the guide members is not specifically
limited in the present invention, and a suitable number of guide
members can be provided on the cutter knife. In addition, the guide
members are not necessarily disposed at regular intervals on the
outer peripheral portion of the casing 10.
While all the guide members 21 to 24 shown in FIG. 3 are extending
in clockwise direction on the outer peripheral portion of the
casing, these guide members can be extending counterclockwise
direction. Otherwise, all the guide members are not necessarily
extending in the same direction. Some of the guide members can be
extending clockwise direction, and others can be extending
counterclockwise direction on the casing. However, the cutter knife
can be more conveniently handled when all the guide members are
extending in the same direction.
<<Modified Embodiment Provided with Handle>>
FIG. 6 shows a modified embodiment, which is provided with a handle
2, by which the cutter knife 1 is handled to cut a quilt.
The handle 2 comprises a grip portion 50 to be grasped by a user,
and a holder portion 51 for holding the cutter knife 1, which is
provided on one end of the grip portion 50. The holder portion 51
has two opposing disc-like plates 51a and 51b, which have center
through holes 53a and 53b, respectively.
As shown in FIG. 6, the side wall of the cutter knife 1 on this
side in the drawing paper has a threaded hole 1a to be engaged with
the threaded shaft 52a of the screw 52. On the other hand, the side
wall of the cutter knife 1 on the opposite side in the drawing
paper has a projection (not shown). This projection is inserted in
the through hole 53b, and then, the screw 52 is fastened to lock
the cutter knife 1 unrotatable. After the screw 52 is unfastened to
rotate the cutter knife 1 to shift the angular position of the
cutter knife 1, the screw 52 is again fastened. Thus, the user can
select suitable one guide member from the guide members 21 to 24
for use.
Thanks to the handle 2, the user can firmly hold the cutter knife
to cut the quilt. The structure of the handle 2 is not limited to
one shown in FIG. 6, and any structure of the handle can be
employed, as long as it can lock the cutter knife 1 not to rotate
during the cutter knife is in cutting operation, and can
appropriately adjust the angular position of the cutter knife 1 for
selecting appropriate one guide member.
<<Modified Embodiment Provided with Holder>>
FIGS. 7 and 8 show another modified embodiment, which is provided
with a holder 3 for handling the cutter knife 1 during a cutting
operation. FIG. 7 shows the cutter knife 1 before housed in the
holder 3, and FIG. 8 shows the cutter knife 1 after housed in the
holder 3 and secured thereto.
The holder 3 is a hollow case-like member, which so holds the
cutter knife 1 therein as to expose almost a half of the cutter
knife 1 to external. That is, in FIG. 8, the cutter knife 1 is
housed in the holder 3, such that one guide member 21 of the four
members and the associated slit 21a are exposed to external.
In FIG. 7, the side wall of the holder 3 on this side in the
drawing paper has a center through hole 32a. Similarly, the side
wall on the opposite side has a center through hole 32b.
Like in the cutter knife in FIG. 6, the cutter knife 1 in FIG. 7
has a threaded hole 1a at the side wall on this side in the drawing
paper which is to be engaged with the threaded shaft 31a of the
screw 31, and also has a projection (not shown) at the side wall on
the opposite side in the drawing paper. This projection is inserted
into the through hole 32b, and then, the screw 31 is fastened to
thereby lock the cutter knife 1 unrotatable. After the screw 31 is
unfastened to rotate the cutter knife 1 to shift the angular
position of the cutter knife 1, the screw 31 is again fastened.
Thus, the user can select suitable one guide member from the guide
members 21 to 24 for use.
Thanks to the holder 3, a user can firmly grasp the cutter knife 1
to cut a quilt. Moreover, the safety of the cutter knife 1 is
improved, since the guide members and the edge of the rotary blade,
which are not serving in cutting operation, are perfectly shielded
from the external.
The structure of the holder 3 is not limited to one shown in FIGS.
7 and 8, and any structure of the holder can be employed, as long
as it can lock the cutter knife 1 not to rotate during the cutter
knife is in cutting operation, and can appropriately adjust the
angular position of the cutter knife 1 for selecting appropriate
one guide member.
Since the cutting operation is carried out using one exposed guide
member, it is needed to expose one guide member and the associated
slit to the external at minimum, when the cutter knife 1 is secured
in the holder 3. But, how degree the cutter knife 1 is exposed from
the holder 3 can be conveniently determined.
Note that, in the present invention, it is sufficient only that one
cutter knife comprises a plurality of guide members having
different widths, and blade edge is exposed in the respective slit
formed alongside each of the guide members. Thus, the cutter knife
of the present invention does not always comprise a single rotary
blade 15, and a plurality of separate blades can be disposed in the
respective slits. In that case, the shape of the casing of the
cutter knife can be variously formed, other than circular.
Second Embodiment
An Improvement to Effectively Utilize Up Almost of the Blade
Edge
The rotary blade 15 can be secured to the casing 10 of a cutter
knife to be rotatable during a cutting operation, or otherwise, can
be unrotatable during a cutting operation.
When the rotary blade 15 is secured to the casing to be unrotatable
during a cutting operation, the sharpness of the blade edge can be
recovered as follows, when the sharpness of the blade edge has been
deteriorated: the holding position of the rotary blade is slightly
shifted to expose a fresh edge portion of the blade in the
respective slits 21a to 24a to thereby recover the sharpness of the
cutter knife. However, since human eyes can not recognize the
degree of the degradation of blade sharpness, some idea is needed
to prevent the deteriorated edge portions of the blade from again
exposed in the slits 21a to 24a. The second embodiment of the
present invention is devised in order to prevent such the
disadvantage. The second embodiment will be described below with
reference to FIGS. 9 and 10.
FIG. 9 shows an exploded perspective view of the second embodiment
of the present invention. FIG. 9 substantially differs from FIG. 2,
in that a dial member 60 and a blade cover 70 are additionally
provided. Thus, explanations will be made on only these different
structures. FIG. 10 is a perspective view showing the dial member
60, the casing member 110a and the blade cover 70 in FIG. 9, from
the opposite side.
<<(1) Relationship Between the Dial Member 60 and the Rotary
Blade 15>>
The dial member 60 has three projections 61 on its reverse side,
and the three projections 61 are to engage respectively with the
three notches 15b formed to the center hole of the rotary blade 15.
After the cutter knife is assembled, the rotary blade 15 always
rotates together with the rotation of the dial member 60 in the
directions "A" and "B" in FIG. 9.
<<(2) Structure of the Blade Cover 70>>
The blade cover 70 is formed having a diameter equal to or a little
larger than the diameter of the rotary blade 15, and having a
cutoff portion 75 formed at one position of its outer peripheral
portion. After the cutter knife is assembled, the edge 15a of the
rotary blade 15 is exposed to external only at the cutoff portion
75 of the blade cover 70, and thus can be used for cutting
operation only at this position.
The blade cover 70 has two pairs of elastic projections (71, 71)
and (72, 72), which are formed on its side face. Each of these
elastic projections 71, 71 and 72, 72 is provided as follows: the
side face of the blade cover 70 is cut in U-like shape to form an
arm-like portion, and an axially raised tip portion 71a, 71a or
72a, 72a is provided on the free end of the arm-like portion.
The location of the first pair of the elastic projections 71 and 71
in radial direction on the blade cover is different from that of
the second pair of the elastic projections 72 and 72. That is, the
elastic projections 71 and 71 are disposed in opposed to each other
on a concentric circle, and the elastic projections 72 and 72 are
disposed in opposed to each other on anther concentric circle
having a smaller radius.
<<(3) First Ratchet Mechanism>>
The first pair of elastic projections 71 and 71 constitutes a first
ratchet mechanism, in cooperation with the recesses 111 formed on
the reverse side of the casing member 110a. That is, after the
cutter knife is assembled, tip portions 71a and 71a on the elastic
projections 71 and 71 enter the recesses 111, and thereby, the
blade cover 70 becomes rotatable only in the direction "A" in FIG.
9 (a first direction) relative to the casing member 110a, and
becomes unrotatable in the opposite direction "B" in FIG. 9 (a
second direction) relative to the casing member 110a.
In this regard, this kind of the ratchet mechanism is generally
known: the tip portion 71a is engaged in the recess 111 to thereby
inhibit the relative rotation of the blade cover 70 in one
direction, while the tip portion 71a escapes from the recesses 111
by the cam action, which is realized by an inclined face provided
on side wall in the recess 111, thereby the relative rotation of
the blade cover 70 in the opposite direction is allowed. Of course,
it is possible to employ other ratchet mechanism having a similar
function.
<<(4) Second Ratchet Mechanism>>
The second pair of elastic projections 72 and 72 constitutes a
second ratchet mechanism, in cooperation with the annular teeth
portion 62 formed on the reverse side of the dial member 60. That
is, after the cutter knife is assembled, the tip portions 72a of
the elastic projections 72 are engaged with the annular teeth
portion 62, such that the dial member 60 can drive the blade cover
70 to rotate only in the direction "A" in FIG. 9.
More specifically, when the dial member 60 is rotated in the
direction "A" (the first direction), the blade cover 70 is driven
to rotate therewith in the direction "A". To the contrary, when the
dial member 60 is rotated in the opposite direction "B" (the second
direction), the blade cover 70 is not driven and remaining
there.
This ratchet mechanism is also well known. Each tooth of the
annular teeth portion 62 has an inclined face and an upright face.
The upright face is engaged with the tip portion 72a to thereby
inhibit the relative rotation in one direction, while the cam
action by the inclined face disengages the tip portion 72a from the
annular teeth portion 62 to thereby allow the relative rotation in
the opposite direction. Of course, it is possible to employ other
ratchet mechanism having a similar function.
<<(5) Manner of Use>>
Since the rotary blade 15 can be utilized for cutting only in the
cutoff portion 75 of the blade cover 70, the dial member 60 is
rotated in the direction "A" (the first direction) in FIG. 9 to
expose the blade edge 15a in one of the slits 21a to 24a (see FIG.
3). For example, when the guide member 22 is utilized for cutting,
the blade edge 15a is exposed in the associated slit 22a. When
another guide member is used, the dial member 60 is accordingly
rotated in the direction "A" to expose the blade edge 15a in a
desired slit. It must be noted that, regardless which of the guide
members is used, the same edge portion of the blade is always
utilized for cutting operation.
As already described, when the dial member 60 is rotated in the
direction "A", both of the rotary blade 15 and the blade cover 70
rotate together in the direction "A". Thus, the same edge portion
of the blade can be always utilized for cutting operation, by
rotating the dial member 60 in the direction "A".
When the sharpness of the edge portion in the cutoff portion 75 has
deteriorated due the frequent use, a different edge portion of the
blade can be located in the cutoff portion 75 of the blade cover
70, by rotating the dial member 60 in the direction "B" (the second
direction).
As already described, when the dial member 60 is rotated in the
direction "B", the rotary blade 15 is rotated together with the
dial member 60 while the blade cover 70 is still remaining there
without rotating. Therefore, the rotary blade 15 is rotated in the
direction "B" relative to the blade cover 70, and consequently, a
different portion of the blade edge 15a is located in the cutoff
portion 75 of the blade cover 70.
Thereafter, like as above-mentioned, the dial member 60 is rotated
in the direction "A" to expose the fresh edge portion in a desired
slit selected from the slits 21a to 24a (see FIG. 3) for cutting
operation. When the sharpness of this edge portion has
deteriorated, the dial member 60 is rotated in the direction "B",
in order to locate further fresh edge portion in the cutoff portion
75 of the blade cover 70 for cutting operation. Repeating the same
steps, all of the circumferential edge portion 15a of the rotary
blade can be effectively utilized up.
For example, when the pitch of the second ratchet mechanism is set
in an appropriate value, a fresh edge portion of the blade can be
located in the cutoff portion 75 for cutting operation, with only
one click of rotation of the dial member 60 in the direction
"B".
Preferably, an indicating means is provided on the dial member 60
(or other locations), which indicates that the dial member 60 has
been rotated up by one rotation in the direction "B" relative to
the blade cover 70. When the dial member 60 has been rotated up by
one rotation in the arrow direction B relative to the blade cover
70, it means that the overall circumferential edge 15a has been
used up. Thus, the user would know that it is time to exchange the
rotary blade with a new one.
Note that, also in the second embodiment, the shape of the casing
of the cutter knife, the number of the guide members, and the
direction or intervals of the guide members are not limited to
those shown in the figures, and they can be appropriately modified,
like in the first embodiment. Further, a modified embodiment, which
is provided with a handle (see FIG. 6) or a holder (see FIGS. 7 and
8) would be also possible.
Although the present invention has been fully described in
connection with the preferred embodiment thereof with reference to
the accompanying drawings, it is to be noted that various changes
and modifications are apparent to those skilled in the art. Such
changes and modifications are to be understood as included within
the scope of the present invention as defined by the appended
claims unless they depart therefrom.
* * * * *